I wrote the code to install the callback and the callback gets called when a RAW file is read. Now, from the callback, when the wanted tag is seen, how to I call the datastream read method to read the tag value. The call back receive a pointer to LibRaw_abstract_datastream input stream. The question is how the datastream read method is called from the callback code which is [equivalent to] C code and as such has to use LibRaw C-API. I don't see anything in LibRaw C-API to use a datastream.
I wrote the code to install the callback and the callback gets called when a RAW file is read. Now, from the callback, when the wanted tag is seen, how to I call the datastream read method to read the tag value. The call back receive a pointer to LibRaw_abstract_datastream input stream. The question is how the datastream read method is called from the callback code which is [equivalent to] C code and as such has to use LibRaw C-API. I don't see anything in LibRaw C-API to use a datastream.